Amicable numbers

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Notion

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Science and technology

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What Wikipedia says

In mathematics, the amicable numbers are two different natural numbers related in such a way that the sum of the proper divisors of each is equal to the other number. That is, s(a)=b and s(b)=a, where s(n)=σ(n) − n is equal to the sum of positive divisors of n except n itself (see also divisor function).

Excerpt from the Wikipedia article “Amicable numbers”, under the CC BY-SA 4.0 license. Read the article on Wikipedia

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